Capacitive pressure sensor and input device including the same

Abstract

There are provided a pressure sensor and an input device including the same. The pressure sensor includes: a first conductive substrate having flexibility; a second conductive substrate disposed in parallel with the first conductive substrate; and an elastic dielectric layer disposed between the first and second conductive substrates and including a plurality of structures having a pyramidal shape, wherein the structures of the elastic dielectric layer are deformed according to pressure applied to the first conductive substrate to generate a change in capacitance between the first and second conductive substrates. Accordingly, the pressure sensor is capable of efficiently sensing a small amount of pressure.

1 . A pressure sensor comprising:
 a first conductive substrate having flexibility;   a second conductive substrate disposed in parallel with the first conductive substrate; and   an elastic dielectric layer disposed between the first and second conductive substrates and including a plurality of structures having a pyramidal shape,   wherein the structures of the elastic dielectric layer are deformed according to pressure applied to the first conductive substrate to generate a change in capacitance between the first and second conductive substrates.   
     
     
         2 . The pressure sensor of  claim 1 , wherein the structures of the elastic dielectric layer have a conical shape. 
     
     
         3 . The pressure sensor of  claim 1 , wherein the structures of the elastic dielectric layer have a poly-pyramidal shape. 
     
     
         4 . The pressure sensor of  claim 1 , wherein the first and second conductive substrates have voltages having different levels applied thereto. 
     
     
         5 . The pressure sensor of  claim 4 , wherein the second conductive substrate has a voltage having a ground level applied thereto. 
     
     
         6 . An input device comprising:
 a plurality of pressure sensors; and   a circuit part sensing a change in capacitance generated in the plurality of pressure sensors,   wherein each of the pressure sensors includes:   a first conductive substrate having flexibility;   a second conductive substrate disposed in parallel with the first conductive substrate; and   an elastic dielectric layer disposed between the first and second conductive substrates and including a plurality of structures having a pyramidal shape.   
     
     
         7 . The input device of  claim 6 , wherein the circuit part senses a change in capacitance generated between the first and second conductive substrates due to deformation of the structures of the elastic dielectric layer by pressure. 
     
     
         8 . The input device of  claim 6 , wherein the circuit part includes a charge pump circuit. 
     
     
         9 . The input device of  claim 6 , wherein the circuit part applies different voltages to the first and second conductive substrates and measures changes in the applied voltages to sense a change in capacitance between the first and second conductive substrates. 
     
     
         10 . The input device of  claim 6 , wherein the plurality of pressure sensors are disposed on a two-dimensional plane. 
     
     
         11 . The input device of  claim 10 , wherein the circuit part determines a coordinate of pressure applied to the two-dimensional plane, based on the change in capacitance sensed in the plurality of pressure sensors.